Well, as most of you by know have realized, the Official 4.3 has been released! As it turns out, I was correct that the Leak#2 was to become our official build! What this means is that the Roms built from the leak and the Roms built from stock will essentially be identical. I have decided to build one from the official since I know most of you would prefer it that way anyway. I will keep the leaked versions posted for now as well, in case anyone wants to use them. Should you use one over the other? I doubt it. Ill say to use the rom built from official source though, simply because it is official.
Some of you will have already updated by flashing the official firmware via Odin, or by receiving the OTA update. Some will have been lucky enough to come in later and found it not to be the best idea to update yet. Because of this I will be including instructions for each situation. It may seem a little confusing at first, but just take it at face value and don't try to read extra into it and you should do fine!

WARNING!!!
If you have NOT updated via the official firmware or OTA update, it is highly recommended that you do NOT do so at this time! You can still run these roms and gain every advantage, with none of the problems!

Instead of flashing the full firmware or OTA, I recommend flashing the deodexed, Knox free build of this Rom for now. I believe it should be the perfect replacement for the official update if you just want to run stock rooted. It has been proven to run smooth, fast and stable! Many have reported it to be the best build to date for our S3, and personally, I agree!
Alternatively, please check out @saranhai's Rom, .::StockMOD ROM::. | TouchWiz 4.3 | Stock & Slim Versions | UVUEMJC as well. It uses mine as a base, but is a bit more customized.

If you have already updated via OTA or Odin flashing the official firmware:

Flash the T999_Official_Deodexed Rom
Flash the slightly older MJ4 modem, IF YOU CHOOSE. This is not necessary though.
Enjoy and report back to me if WiFi and everything seems to be working ok.

If you have NOT updated to the official release yet:

Flash the T999_Official_Deodexed Rom
Flash the MJ2 ATT kernel
Flash your choice of the two modems in the OP.
Enjoy!

Based on the Leaked Build

Please thank @Prod1702 if you see him! Without his willingness, determination, and commitment to XDA, I would not be able to present you with this brand new build! He seriously stuck it through well beyond what I would've ever expected anyone to put up with! Please take a moment to go HERE and hit his Thanks button to show your appreciation! Without him, this rom, And MODEM, would be nonexistent in these forums!!!~~~

Although the previous leak proved to be amazingly stable, and this one appears to be no different, please remember this is after all, still a leaked test build of the 4.3 Touchwiz system! There may be new bugs, new features, better or worse performance, etc, etc.

I do have reason to believe this may in fact become our official build, or if it does not, it is very close to it! I will try to explain more on this and what I expect to see a bit later. But I have been running this build for most of the day, and am seeing similar results as before where battery and stability are concerned!

So with no further ado, here is your latest leaked build of 4.3 Touchwiz! Note, these are complete T-Mobile builds, but I have had to continue using the AT&T insecure kernel due to issues pulling/dumping the one that goes with this build. As before, I have seen absolutely no problems arise from this.

This is 100% the full MJC build (except kernel). I have not removed Knox or anything, and I have left it Odexed. Zero changes! This is more for devs or anyone who wants to dig into how Knox works and is affecting things. Or for those who just want to see what the full stock build is like. Understand that Knox and seLinux do interfere with root. So if you have problems with your root apps, I suggest you try the deodexed, Knox Free, build below. (I will provide a separate secure kernel later for flashing for those who want to set seLinux to enforcing.)

This ROM has NOT been debloated. Only Knox, CIQ, and SysScope have been removed. Deodexed, full build.

Installation

If you are currently on a Non-Touchwiz Rom, you will have to Factory Reset
Because this is a Leaked build, I suggest starting clean. Preferably with already up to date MD5 firmware.
If you are not, Please Odin flash the MD5 root66 firmware. (Link to thread in my signature).

Download your choice of ROM, and the MJC (or MJ4) Modem.
Flash in CWM/TWRP Recovery exactly as you would with any other Rom or Modem!
Thats it! Nothing special!

This is 100% the full MJ4 build (except kernel). I have not removed Knox or anything, and I have left it Odexed. Zero changes! This is more for devs or anyone who wants to dig into how Knox works and is affecting things. Or for those who just want to see what the full stock build is like. Understand that Knox and seLinux do interfere with root. So if you have problems with your root apps, I suggest you try the deodexed, Knox Free, build below. (I will provide a separate secure kernel later for flashing for those who want to set seLinux to enforcing.)

Huge Thanks to @Prod1702 for leaking this build, and for all of his work and effort working with me to get what we need off of the phone!
Thanks is also highly deserved by these guys as well!
@TheLastSidekick, for his friendship, advice and becoming our newest RC!
@saranhai, for being such a cool guy to team up with on this stuff, and for all of his fantastic work and advice!
@loserskater and everyone responsible for the AT&T leaks for beating me to the release of a leak! Because without them ours is not possible!
@stratatak7 for his work on the AT&T kernel, without which we would have NO T-Mobile leaked roms!
@upndwn4par also for his work on the AT&T kernel, without which we would have NO T-Mobile leaked roms!
And a big Thanks to all of the members who have taken the time to try out this and all of Team Inferno's roms and report on your results!!!

This is a copy/paste of the changelog as listed at SamMobile.com for the I9300 update. Most likely, we will see the same features and improvements, but this is by no means guaranteed. Also, and once again, I remind you that what we have are LEAKED test builds. They may not be complete, so if something is not in the leak, it does not mean it will or will not be in the official release!

We have had only a few reports of the following:
Problems with dropped calls
Reboots/bootloops
Losing Root

Note: It appears that ALL 4.3 releases have now been delayed due to many problems with the I9300 rollout. Just about everything reported that led to this on the I9300 has not been observed with ours. Hopefully they won't delay ours much longer since it appears it is a very stable build for our models! No one has got the update as scheduled, so I don't expect us to either.

This leak is primarily for the T999 ONLY. You can flash to a T999L/N/V, but will have no mobile data connection.
Most who are not on a T-Mobile network have reported issues with the SIM card not being detected. (Needs Re-Verification)
You MUST flash the UVUEMJ4 Modem/Baseband. No others will work at this time. (Needs Re-Verification)
I suspect that some of the more random issues may be due to older firmware.
I recommend flashing the UVDMD5 firmware if you haven't already done so. Update via Recovery. Update via Odin.
Knox may prevent some root apps from keeping persistent root privledges.
If using a secure kernel, seLinux is set to "enforcing" and side by side with Knox, will make life Hell!!!
Suffers from the profile folder problems. /0/0/0/0/0/0/0/0 Every time you flash a 4.3 build, it will create a new /0 folder abovethe current one and will use this location by default. Manually copy /data/media/ to /data/media/0 after every flash.

Remember this is a NEW leak/build. If you experience a problem you had on the last one, please report again.
Let me know if I have left anything out or if you find anything not yet mentioned.

A note about reporting bugs
If you dirty flashed (did not factory reset), or if you have applied any mods, please do not report bugs. Reflash clean and test first. If you discover a bug caused by a mod, please let us know, but flash clean so you can be sure if it is the Rom, the mod, or something else entirely.

Can I flash this to my T999L, T999N, T999V?
Well, sort of. You can flash it if you want to see what 4.3 will be like. But without a 4.3 modem for your specific device model you will not have any Mobile Data connection at all.

Can I flash the MJ4/MJC Modem to my T999L, T999N, T999V?
In short......NO!

Will the MJ4/MJC Modem work on older ROMs/Firmware? e.g. 4.1.2 based Rom with MJ4 Modem.
YES! But ONLY if you have the T999!

Why do I get a notification that root access has been blocked?
Welcome to Fort KNOX! If this is a problem you cannot live with, either remove Knox from the Odexed build, or just flash the deodexed ROM. If you are running a ROM which has seLinux enforcing (secure kernel) and Knox installed....well....have fun!? This combination is a PITA to deal with and will prevent nearly all apps attempts at root access! I do NOT recommend this configuration!!!

I just flashed X ROM and now all of the data on internal sdcard is gone! What happened to my data?!?!?Don't Panic! It did NOT delete any data! The ROM created a new /0 (zero) folder and by default connects to this as the root of your internal sdcard. You need to copy your data from /data/media to /data/media/0/. You will find all of your files are still intact, they just were not being seen because of the messed up folder structure.

Keep in mind that my battery is over a year and a half old! But this is 19-20 hours on battery, using 5.5 hours of screen on time (a good bit was set at fairly high brightness), and as usual, using TapaTalk which isnt really the most gentle app when it comes to battery use!

Conclusions So Far
As it was with our first leaked build, the rom itself seems to be surprisingly excellent on battery! The Day 1 battery once again helps to showcase the ROM's battery use, on its own (plus Tapatalk). So if you were to flash it and make good use of Settings, you should see similar results. I find it very reassuring to see how consistent the battery cycles have been so far!

This is the ROM I was personally using before I bricked my device. It does not have any major modifications, just some, perhaps interesting debloating. I was not totally finished with it, but thought I would share in case anyone else wanted something like it. Basically, I was removing things I do not use, but that could potentially be running in the background, using resources and battery. A couple of examples of this would be Googles Backup Transport service, Contacts and Calendar sync, Accuweather, NameID, etc, etc, etc. I will try to post a full list later. I know much of this could be debated, but it seemed to be just as stable as before, and everything I made use of still worked.
Its kind of a different take on the debloating of a rom.

Note: I am not giving credit on most of these simply because many can be found all over the place! I have been collecting them myself for a while now, just for my own use, and the ones I did not discover on my own, I cannot remember where I originally saw. If this is a problem, or you feel you deserve credit for a particular discovery, please let me know and I will be happy to work it out with you. These are very easy for anyone to find on their own though. I have quite a few more that I might post at another time.

I Love This Stuff! And I am just happy that I got the opportunity to be the one of the ones to work on it!

Couple things real quick. This has so far been great for my own use, but I have not done much to stress it. Been mostly trying for a good baseline Day 1 battery report like I did for the first leak. So far it seems to be right on par with it.

I will get to updating posts 2-5 with more information later on. I will check back periodically to make sure nothing catastrophic happens, but aside from that I'm planning to spend some time with my daughter before bedtime since I get to have her an extra day for the holiday weekend! Once she's asleep Ill get back to work on the fun stuff!

Hope you guys enjoy it! And I hope you don't mind me keeping the leaks in separate threads. I felt it best for different builds since there will likely be different bugs and all. Just less confusing IMO. Ill note each OP of the existence of the other to make it easy to reference.

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